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Control Module - DTC's for MAF Sensor/O2 Sensor

TO: ALL DEALER SERVICE MANAGERS
ALL DEALER PARTS MANAGERS

CC: MBNA FIELD PERSONNEL
VPC / PDC MANAGERS

SUBJECT:
GROUP 07.4 - ALL VEHICLES WITH M119 AND LH: DTCs 4 AND/OR 12 IN LH-SFI CONTROL MODULE, USUALLY COMBINED WITH DTCs 10 AND/OR 22 IN DM

MBAG has confirmed that a component in M119 LH-SFI control modules (N3/1) may fail at temperatures below approximately 50 degrees F (10°C), causing the voltage supply to the Hot Wire MAF (air mass) Sensor (B2/2) and/or the voltage supply to the 02 sensor heater to be lost. This sets a DTC for either the air mass sensor or the 02 sensor heater, or both, in the LH control module and/or the Diagnostic Module. This generally occurs before the vehicle has accumulated 500 miles. In all cases, replacement of the LH control module repairs the vehicle.

At this time, the affected production range is unknown. Updates will be released as further information becomes available. Please report all cases to your Regional Technical Coordinator, with VIN, mileage, part number and control unit date code (on silver label near part number, Example: 94M08).

Please do not replace the Hot Wire MAF or 02 sensors unless testing reveals that they are actually defective.